What is wrong with below code

Question

The code was suppose to rotate a one-dimensional vector of n elements left by i position. for instance, with n=8 and i = 3, the vector abcdefgh is rotated to defghabc.

T

Answer 1

Change

char* string = "abcdefghijk";

to

char string[] = "abcdefghijk"

The former points to a read-only string literal, whereas the later is an array initialized from that literal.

Answer 2

Memory allocated as a variable initializer, like this...

char* string = "abcdefghijk";

...is immutable. That is, you can't change it, and attempts to write to it will result in a segfault. You can only modify memory allocated via malloc() and friends. You can accomplish this very easily with your static string like this:

char *string = strdup("abcdefghijk");

The strdup() function calls malloc() internally and then copies the source string into the target. You're already #include-ing string.h, so the strdup() function prototype is already available without any additional code.

Answer 3

If you want to use a string to manipulate on, use a real character array rather than a character pointer.

    char string[] = "abcdefghijk";